#include <u.h>#include <libc.h>#include <bio.h>#include <auth.h> void	error(char*); int nonone = 1; /* * called by listen as rexexec rexexec net dir ... */voidmain(int argc, char **argv){	char user[NAMELEN], buf[8192];	int n, nn, nonone = 0; 	ARGBEGIN{	case 'a':		nonone = 0;	}ARGEND; 	if(srvauth(0, user) < 0)		error("srvauth");	if(nonone && strcmp(user, "none") == 0)		error("rexexec by none disallowed");	if(newns(user, 0) < 0)		error("newns");	n = 0;	do {		nn = read(0, buf+n, sizeof(buf) - n);		if(nn <= 0)			error("can't read command");		n += nn;		if(n == sizeof buf)			buf[n-1] = '\0';	} while (buf[n-1] != '\0'); 	putenv("service", "rx");	execl("/bin/rc", "rc", "-lc", buf, 0);	error("can't exec rc");} voiderror(char *msg){	fprint(2, "rexexec: %s: %r\n", msg);	exits(msg);}